The Apera Instruments DO850 oxygen meter is equipped with a state-of-the-art optical sensor for dissolved oxygen measurements. The optical sensor has no membrane and requires no special solutions. You will get a stable reading in 1 to 3 minutes. The sensor has a lifetime of up to 8000 hours of operation. The special coating on the cap protects the sensor from external influences and enables measurements independent of available light and chemicals. The meter is waterproof and dustproof (IP57 protection rating), allowing it to work in harsh environments.

Technical Specifications:

Dissolved oxygen (DO)	Measuring range	0 to 200 %; 0-20.0 mg/l
Resolution	0.1 / 1 %; 0.01 / 0.1 mg/l (ppm)
Accuracy	±2% of the display or ±2% of the saturation; ±2 % of the display or ±0.2 mg/l (ppm), the larger value counts in each case
Response time	90 % in ≤30 s (at 25 ℃ )
Calibration points	Saturation point & zero point
Temperature compensation	0 to 50 ℃ (automatic)
Air pressure compensation	60 to 120 kPa (automatic)
Salt content compensation	0-45 ppt (manual)
Temperature	Measuring range	0 to 50 °C
Resolution	0,1 °C
Accuracy	±0.5 °C
more	Power supply	3 x AA batteries
Housing protection class	IP57
Size	88×170×33 mm (with case 360×270×76 mm)
Weight	313 (with case 1,3kg)
Certification	RoHs, CE & ISO9001:2015

A complete set contains:

• DO850 Meter
• DO803 Optical electrode for dissolved oxygen
• Electrode calibration cap
• Small screwdriver
• Sponge as water reservoir (replacement)
• operation manual
• Carrying case

The meter has the EC marking and a warranty of three years on the device (two years on electrodes).